"That is an old human" just got rejected and I am not sure if it is just an oversight, if there is a female version of "člověk" or if it is just something you wouldn't say in english? In any case I reported it and hope for some clarification.
Sounds strange to me unless it is a human in the zoo or it is spoken by aliens. But I am not native English.
"That is a strange human" is highly unlikely to be used... except maybe by someone looking at an exhibit of humans in, say, a science fiction movie, or maybe by someone being sarcastic. :-)